A platform used in agriculture harvesting crops is universally defined as a head attached to a harvesting machine and that serves as a removable attachment for use when cutting requirements are request. It is made and assembled onto a main frame or chassis which is divided into a central section, the area corresponding to coupling with the harvester, and two side sections wings, that projects on either side of said central section according to a perpendicular direction to the advance direction of the harvesting machine. The platform has a cutting mechanism cutterbar projecting laterally across the width thereof, defined in front of the side sections and center section, and is configured to sever the standing crop.
Platforms contain a system for the transverse movement of the crop material. Typically it is formed by a helical screw conveyor and alternately today there exist systems containing a set of canvas or drapers for conveying. Both the canvas draper and the screw conveyor operate to transport the crop cut by the cutterbar and drive it into the center section. Furthermore, it is well known there are multitudes of arrangements where gadgets are used to force the material that reaches the center section of platform to pass through the feederhouse and to the combine's feeder thereof, to be later treshed by the harvester. Each prior art heads prefer one of these devices and determine the input mode of the crop material to the feeder of the harvester.
Finally, it is known that the cutterbar of some cutting platform is configured to flex in response to ground shape. In these, a series of sliding plates skid shoes are linked to said cutterbar to confer the ability to settle above the ground and slipping while operating. All this in view of making the cut of the plant as close to the ground as possible in practice, allowing the collection of those pods with beans sprouting in the lower part of the stem. Thus, when the head is advanced in work, the cutterbar is positioned virtually glued to the ground and curling up to mimic the natural unevenness of the field, resulting into a crop cut at constant height. While this well known in theory, most platform transitions from auger/flex-cutterbar to draper/flex-cutterbar does not respect the good design of the cutterbar of the first. In the chase of shortening the distance between the draper and the cutting zone most manufacturers have not developed a really effective, good angled, low losses cutterbar system.
Harvesting machines and threshing machines particularly relates to the sever and/or the collection of crops. These generally have an attached platform, arranged in the front part, which extends laterally to collect a preferred width of standing crop. This platform employs means of transportation for the delivery of the crop material to said harvesting machine for subsequent separation of grains and other treatments. The harvester/thresher uses a chain conveyor feeder to take the harvested crop in an essentially right angle from the platform.
There have been many mechanical devices designed for the transition from the lateral movement of the crop through the platform to a transverse longitudinal movement with respect to lateral movement, which directs it to the feederhouse, trying to turn ensure an even material flow. The main form of conveyor has a traverse screw type conveyor with a helical strip surrounding a cylinder in which several, at least two, opposite fillets with mounted blades are arranged on the outer surface of a cylinder, so that upon rotation of the drum the material is trapped between the ends of two straight opposite and helices is forced to move normal to the axis of rotation of said cylinder.
A feature which has been found relatively important to the successful transition of movement of the material to the feederhouse is the use of a plurality of retractable fingers configured to extend out of the cylinder of a screw conveyor (auger). These fingers are located in the intermediate section of the auger conveyor tube between the oppositely disposed screw flight on each end of the auger. This particular construction is shown in Patent Alvin W. Oehler, U.S. Pat. No. 2,529,180, Nov. 7, 1950. The core problem of the platforms that use a screw conveyor, with or without retractable fingers, for the transition of the crop material to the feederhouse of the harvester/thresher is its low capacity to manage material flow and the subsequent clogging of the mechanism.
Another form of cross conveyor mechanism was developed by Harvey Herndon, published as U.S. Pat. No. 2,671,553 on Mar. 9, 1954. This conveyor is constructed by a conveyor belt which covers the whole width of the feederhouse opening of the combine harvester and which is configured to run so that the upper portion of the belt carries the material to said feeder.
As it was found that the transverse feed belt itself was not able to feed and control the crop material volume delivered to the feeder, considerable width platforms are built especially with a secondary feeder apparatus including a rotatable member (cylinder) having retractable fingers and/or pallet members and which is mounted above the rear end of said central draper belt. Such a structure was revealed by Roger L. Patterson granted as U.S. Pat. No. 5,005,343 in Jul. 17, 1989 and as U.S. Pat. No. 4,956,966 in Sep. 18, 1990. This mechanism confines the material running over the cross conveyor belt and helps in feeding into the inlet opening of the feederhouse of the harvester. However, a design of this type has not been found capable of handling heavy crops without accumulation and jamming in front of the entrance to the feed channel. It is known that due to the nature of chain type of the feeder carrier of conventional harvesters, crop material has to be forced at the entrance of said feeder carrier for chains to be able to catch and transport it quickly. In an attempt to quickly feed material into the inlet opening, it was tried to drive the transverse conveyor belt at relatively high speeds.
Since increased flow velocity of the cross conveyor belt has not completely overcome the problem of clogging, an attempted solution has been developed by Gregory J. Honey, published as U.S. Pat. No. 5,464,371 in Nov. 7, 1995. In this structure there is one rotating drum disposed between the transverse belt conveyor platform and the inlet opening of the carrier feeder of the harvesting machine, whose rotation speed is set independently, and further characterized in that it has retractable fingers as means for engaging and dragging the material. However, even with the proposed improvements, the existence of the additional conveying element did not solve the lack of compression to the transverse flow material against the opening of the feeder carrier, a problem that grows when the crop is of bushy type, such as wheat, barley, or high yield soy bean and that cause jamming because the low ability to direct the entire flow of material.
There has been a continuing need to improve the technique of cross-mobilization mechanisms to reduce the complexity, and thus reduce the possibility of mechanical failure or jamming of the material, crop, between components. For example, Steve Tippery, Kaster Craig, Adam Lee Haworth, Cristoph Nathan and Jens Petersen, granted to CLAAS SELBSTFAHRENDE Erntemaschinen GMBH, Germany, revealed a solution mechanism in U.S. Patent U.S. Pat. No. 7,587,885 from Sep. 15, 2009. They determined, surprisingly, that the removal of the cross-carrying belt (central) improves feed efficiency of crop to the feeder carrier towards the harvester, and also produces a smoother transition from the lateral flow of material toward the cross-flow. The proposed mechanism is constructed using a cylindrical feeder drum, which combines the use of opposite helical flights and retractable fingers, and a floor-tray contoured that has two circular walls to force the material to change direction. However, it was found that the proposed solution mechanism is not able to handle large volumes, which have crops such as wheat, barley and high yield soy bean. In this mechanism, the working condition worsens to critical terms when it is necessary to advance the platform at high speeds, since the material (crop) begins to accumulate in the area near to the opening of the feederhouse until a point where the growth of mass of accumulated, unswallowed material is such that it is reached by the reel, which is followed by the latter engaging and throwing it forward, determining a circuit which is repeated while the volume of said material is not decreased (which always means slowing down harvest speed).
Lately, Deere & Company revealed a new approach that insist on the usage of a central canvas. This disclosure was published as US20140237979 in Aug. 28, 2014. The innovation consist of two new conveyor members (drums with a rotational axis substantially vertical) located at a crop transition zone between the side draper conveyors and the rearfeeder drum with retractable fingers. The crop coming from the left and right endless belt conveyors thus needs to change its direction in the center of the platform from a lateral direction into a rearward direction. Under unfavorable circumstances, this area can be due to lack of moving feed elements between the rear end of the center conveyor and the upperfeeder drum subject to crop stalling, which allows crop to leak from the platform, causing crop losses and/or material to lodge in the left and right endless belts with the result of belt stalling. With the use of this new transition conveyors, which are disk-shaped and have fingers that are distributed around their circumference, John Deere platform could improve the flow of crop material at the transition zone. However, having studied other similar mechanisms, it is for sure that this new development will do nothing to help the mobilization at the dead zone (the central portion of the platform, just behind the cutterbar and before the central draper conveyor).